Modifying prebuilt junk, in stages, to be less junk like.

[SternWake]

My feet tend to find their own happy spot regardless of what my conscious brain thinks.

The Mini’s kicktail is pretty narrow with no concave, and my footwear, well, let’s call it not as protective as it should be, and my back foot is just not very happy way back on the kicktail.

Even on short surfboards my back foot was always atop the rail fins or just in front of them, where most back footed surfers would keep theirs as far back as they could get it. If I kept my back foot where they did, I found I would just lose all forward drive as I could easily overpower the fins, and larger fins would just get stiff and draggy and slow.

I worked with a lot of shapers before designing and building my own boards trying to find a design and fin combo, where my back foot was ‘where it was supposed to be’ and it just felt wrong.

Lack of flow.

Forced.

Unnatural

I finally got old enough where I decided that my back foot was pretty damn smart, and just let it do what it wanted.

Many years of muscle memory, and habit, are telling me to let my feet choose where they want to be on the mini.

I am not sure that I am willing to fight it.

[SternWake]

6 degree Bubinga wedges

Was waffling over thickness, and angle. as this is my last piece of Bubinga.

Dewedged rear truck first and the test ride was very positive.

Then wedged front truck and definitely felt more of what I have been seeking when carving this board and pushing it harder and harder when the wheels and legs warm up.

I have enough room to remove the rubber risers and not get wheelbite until I am going walking speed, where wheelbite is not a factor.

This thing is laughing at the crushed shell trail in its current state, on torque level 3 of 4. It can get squirrelly carving on the loose shells, but very predictable so.

The rear sleeves once looked like the these front wheels.

I swear, Although Fiona appears to have become one with the cool Northwest wind, she is NOT on mushrooms.

She’d have to be holding out on me, and she is just not that type of soul.

I decided to remove the shrink wrap on my premade 7s2p inside my portable charger’s enclosure, and found DMEGC 20P cells.
2000 mah and 20 amps continuous no temp cut, 30 amps with 80C temp cut.

I did not expect to find a recognizable cell manufacturer inside this battery, much less a cell rated at 20 amps CDR.

Even Batemo says 17 amps, 22.5A peak, and they seem to rate cells very conservatively.

This battery certainly never ran hot, So I guess I should not be surprised.

The other premade 7s1P battery I disassembled had BFN cells, 2000mah 10C max discharge rate. One cell had failed, but I made 2 3s1P batteries from them, which still perform well enough 2 years later.

I received 14 EVE 35V from Nelvick today, and some other goodies.

I intend to make a 7s2p in the same format of this battery, but now am thinking maybe I should have ordered Eve 30P instead.

As a 10s portable charger, dialed to ~315 watt output, I am looking at about 7.8 amps max discharge per cell at 3.0vpc to charge my 10s2p assuming V booster is 85% efficient.

Batemo says 7.88 amps continuous ( peak 15. 5) for EVE 35v, datasheet says 10.2 to 60C, Mooch estimates 8.

I can always turn down the output wattage if it runs too hot. I find our walk through the parks while charging are short enough I disconnect it before it is done.

The premade 7s2p battery, if not for the 0.1mm x 8mm wide series and parallel nickel plated steel strips and haphazard balance wire confluency by BMS, has no huge red flags saying immediately place this thing in a metal box outside, and recycle asap. There is only a 24mv P group delta in the 3.6v range.

Part of me is saying to just add some fishpaper , prettify and protect the balance leads, and reheatshrink it and keep hammering it.

Another part is saying rebuild it with 0.2mm copper

[SternWake]

Cold today, for Florida.

So We skipped the morning roll, for when it warmed up a smidge.

I debated on bringing a portable charging source, and decided we would not go very far, and to skip it.

That was the first in a series of bad decisions.

We crossed the south Bridge to the Key, as I had a hankering to see the Gulf with some strong Northerly winds, maybe mindsurf some windswell slop waves.

Traffic had me choose to go north, and full throttle it into the cool wind for 2.5 miles, and I was like F it, we will leave the Key by the north Bridge.

I slowed down to preserve battery, but it was not enough. I already chewed so much of it full throttling into a strong headwind. Wound up walking the last 1.5 miles, and after a mile, Fiona decided she was done walking.

She got to share the chariot with my esk8, as I cursed my poor decision making, and walked the rest of the way home. Google Earth says we got 10.6 miles on battery alone, which is not too bad considering the lengthy full throttling into a strong headwind and we left home at 41.4 volts.

At least the balance of the chariot is near perfect with Fiona and the Esk8 inside, so the wheels took all the weight.

The portable charger needs to become functional again.

I prefer walking when it is a choice, and not a necessity.

[SternWake]

We rolled inland 1.6 miles to a pretty big dog friendly park late morning.

It’s a 45mph road with decent sidewalks, no bike lane.

No car traffic behind us, so we took the main road for 95% of the distance to park entrance, at full throttle.

The grass at entrance is short and the sandy dirt compacted.

The hub motors had more than enough power to roll the pedestrian free sections and well into a narrower trail at potentially unsafe speeds. It was awesome.

I busted out my Samsung 6s1p 50E and dialed my White ‘420’ watt’ V booster to about 7.5 amps input current which is charging the 10s2p at about 167 watts, and we walked the shaded quiet trails for a while.

We walked across the park, then rolled its southern perimeter through some smooth quiet neighborhoods, and then back through park, then rolled the Main road on NW side of the park, and then back into it, before walking some more.

The Samsung6s1P battery was about 3.3 volts per cell, and nearly triggered the 6s BMS LVD at 170 watts, before I could turn it down. Disconnected, its voltage recovered enough that the BMS kicked output back on, and I dialed Booster current to the minimum, plugged it back in to charge at Dialed up about 40 watts of charge current, and we kept walking towards some shaded benches. The BMS LVD kicked off again while I was watching the input side wattmeter and input voltage was 2.74 volts per cell, and the 10s2P was now up close to 40V again.

We walked past all the pedestrians and then rolled to the empty grassy goodness.

I parked Fiona with the chariot in a shady area, and explored a bit solo, with power to spare, and then picked her up and we headed towards home.

Again, I was able to roll the road rather than the sidewalk for a good portion, at full speed, and with plenty of battery left we rolled our own hood for a few more miles, exceeding the speed limit, barking up a storm.

I am starting to think that getting these hub motors over 155F on a sub 75F day around here is unlikely to occur.

I both want more speed, and am thinking it is a good thing I cannot go faster.

I really like the confidence that having a portable charging source allows.

Not having to baby the throttle just in case, is priceless.

The 108wh Samsung 6S1P 50E and the white booster are a pretty capable combo.

The 103.6wh DMEGC20P 7s2P enclosure is more so, and faster to set up and break down and pack away.

Need to make that new 176.4wh Eve 35V 7s2p for it, and see how hard I can run it.

The DMEGC 20P 7s2P might get some copper welded atop the nickel plated steel, rather than removing the nickel plated steel and 0.2mm copperifying it.

I also have a BAK45d 5s2P 162wh Makita battery to build, which would be a very capable portable charging source too, although the higher the White 420 CCCV booster’s input voltage, the better. It has a 15 amp fuse on the input and is rated at 10 amps input. I have a big enough heatsink I will run it at upto 15, but the Samsung6s1p 50E gets too hot about 9 amps, but stays happy and cool at 7.5.

TranceJunkie is supposed to be ~2 dozen miles south of me in a few days, So I want to have both the guppy and the Mini tuned and ready, and portable chargers for both.

[SternWake]

This is the prebuilt Huanyuyuan HYY-7S2P battery’s BMS.

The beige sticky glue near balance connector, was cooked and brittle on the 5 amp Shottkey Diode on lower right at c- terminal.

It still does Diode things as far as I can tell, and smells more like hot electronics, rather than burnt out electronics.

Gonna clean it up more, and maybe attach a little heatsink on Diode and heatshrink it and upgrade this DMEGC 20P 7s2P to fully functional, better than factory status, with 0.2 copper s/p bussbars and balance leads not spagettified in the presence of Main + tab.

Should help me practice, and build the new 7s2p Eve 35V battery better.

The 14 fishpaper ring’d cells were all witin 1mv, but my paralleling jig was already set up, so in they went anyway

[b264]

Do you have a photo of the bottom of that PCB?

[SternWake]

No signs of heat damage below

[b264]

Nice. What is this though?

[SternWake]

It is a perfectly round piece of missing PCB mask which came off when I peeled off the squishy adhesive foam piece in order to take the picture. Can see it stuck to the foam.

I was inspecting 7s2p prebuilt’s welds more closely and it looks like the machine used was making 4 dots, two pair of spot welds at once, but the 4 prongs were not always held perpendicular and not exerting equal pressure and the welds were not even and equal

A few cells had one pair/ two dots and the rest were 4, but two strong and two weaker.

So I ripped the whole damn thing apart dremelled the cells free of old welds, and when separated, all 14 cells are within within 2 mv of each other.

So again , put all 14 in my paralleling jig for no particularly good reason other than it is here, and I might be able to pretend the total effort is worth it..

So rebuilding the 7s2p dmegc20p will be overall far more work than building the new 7s2p eve35V, and neither will directly power an Esk8, only built to power the portable charger to charge my esk8 when I am in the park walking the sweet goofball.

Not gonna be ready for tomorrow, but the Samsung50E 6s1p is ready to add a few miles.

[rafaelinmissouri]

Are all these adventures on the tiny deck? Or which set up?

[SternWake]

Most Adventures happen on the Guppy, as it is way more comfortable and capable.

[rafaelinmissouri]

I appreciate and enjoy the pictures.

Such sunny skies.

[trancejunkie]

[SternWake]

Great meeting you in person, @trancejunkie, and barking up Venice Beach with you and Fiona.

You certainly like tight trucks. I just took the Mini to beer store and struggled, as I am so used to a roadside cup washers on the verge of rattling. Loosey goosey.

We cruised 9.6 miles, and the mini had at least 1/2 mile more in the 10s1p EVE 40PL, and is still not flashing 1bar, and the ESC isnt beeping low Battery.

The Guppy was charged back up to 41volts by the time I parked the van, and we rolled the 4 miles home with throttle and range to spare.

Fiona did not seem to mind sharing the chariot with the Mini velcro cinch strapped to the side for 8 miles.

She’s all Fired up right now, wanting to play ball and tug o war.

[SternWake]

The Mini’s trucks were dialed back to my preferences for an out front carve session, then after an incomplete recharge, it towed the FionaYak to the kayak launch, and then spent some time inside the Kayak Hatch.

I got a shoulder MRI yesterday, and took it pretty easy on it paddling today.

Thankfully, paddling the kayak does not make it feel like upper biceps tendon, and or supraspinatus rotator cuff muscle, were getting abraded rolling back and forth over humeral head like which has been happening in many other daily activities and depressing the shit out of me.

So we charged headlong into wind and tide to hunt a cormorant perched on a distant channel marker, and barked the living shit out of it.

I’ve lost a lot of paddling conditioning, and have gained weight.

So has Fiona, and even though the mini is lighter than the midsize kicktail that usually tows the kayak, we were sitting lower in the water.

Pretty strong wind and choppy surface had us seek the protection of the mangrove tunnels downwind, , and just absorb the quiet.

The last time the Mini was the Kayak tow vehicle, it was the diagonal drive Mini, 70mm urethane, with a 7s2p DMEGC 20P battery, and an annoying max speed of 12mph.

It now has a EVE 40PL 10s1p, 105mm urethane, with torque, speed, and range to spare.

The prebuilt ‘Huanyuyuan’ 7s2p DMEGC 20P cells, has been rebuilt with 0.2mm copper, and is back inside my 300 watt portable charger.

The rebuilt Dmegc 103.7wh 7s2p will soon be replaced with a 176.4wh 7s2p EVE 35V.

The Dmegc pack can quickly return 2 amp hours into my 9 amp hour 10S2p BAK45D.

I might have to dial portable charger output down from 300 watts output, if EVE 35V 7S2P battery runs too hot powering the CCCV booster at upto 15 amps input.

Time will tell.

[SternWake]

The kayak outing revealed the chariot’s Vevor rims have cracked bearing seats. Same rims as on the Guppy.

A while back I bought a used MBS analog MTB for the TKP AS.12 trucks with a 12mm axle, but never employed any part of it. I did put the hanger on the Guppy with the MBS200x50mm tires but went right back to the Vevor hanger with the Kendas, and tried to forget about the poor decision to buy it.

I thought it came with Rockstar2 hubs, but tonight discovered they are actually 5 Star hubs, which can better accept the 2.80/2.50-4 and 4.10-3.50-4 tires I am using on the guppy and the chariot.

The Vevor TKP trucks have a 10mm axle and rims a 26mm OD bearing.

The 5 Stars came with no bearing spacers but I just ordered 12x22.5mm spacers from MBS, so I guess I will swap the AS.12 truck onto the guppy, even though One tried to kill Venom1212.

The chariot Hanger has the Vevor truck, cut in half, installed within it, and thus 10mm axles.

I am considering how to best implement the 5Stars

A 10mmID, 12mm OD tube might be ordered too. This can allow me to use the Sixshooter 6x2 spare tire should the chariot get a flat, and if the guppy gets a flat I can put transfer a chariot tire to the guppy, remove the sleeve and use the sixshooter on the chariot.

Or perhaps carry a second spare with 12mm ID bearings.

Or just skip using the AS.12 truck and keep 10mm axles all around and use 16100 bearings.

Anyone have cracked bearing seats in their hubs and just locktite the bearings in place them and forget about it?

Seems unlikely.

[SternWake]

I have completed the 7s2p EVE 35V for inside my portable charger, and tested it yesterday.

The output wattmeter claims it delivered 3.793 amp hours and 153.2 watt hours to my BAK45D 10s2p, at a starting rate of 200 watts.

The DMEGC20p 7s2p twice claims to have delivered 2.06 and 2.08 amp hours, but at a starting rate of 290 watts which crept as high as 315 as esk8 battery voltage rose.

It was a cool day for Florida, and I measured as high as 52C on the Eve 7s2p, but the hottest spots of the battery were those closest to the booster, which was reading as high as 75C on parts of it.

The XT60’s act a bit like a radiant barrier and the area behind them was several degrees C cooler.

So line of sight of the booster’s inductor reads significantly hotter via a IR thermometer, when hunting.

I think even with a radiant and convective heat barrier between Vbooster and battery that it will be too easy to reach 60C with a 7s2p of EVE 35V, and that this was a poor choice of cells for this application, if I want to be able to portable charge at 200+ watts.

As it was, the esk8 battery was not depleted enough to accept 200 watts for the full output of the 7s2p, and wattage had tapered to 72 when the BMS LVD kicked in and cut all power to the booster at somewhere below 2.78 volts per cell average..

At 200 watts the Booster external heatsink did not seem too hot, while at 300 I cant leave my asbestos fingers on it for very long.

I did not want to spend a lot for prime cells for this portable charger, but in retrospect the EVE 30P would have been a far better choice for about $5.50 more for the 14 cells, but Nelvick was out of 30P stock at the time anyway, So it is ALL his fault. :)

I lowered the output from 300 watts to 200 right at the start of the test, being the first discharge cycle and my data free belief that they should be treated kinder the first cycle.

I just charged it back upto 29.4v. It claims to have taken 6.78 amp hours ( rated at 7) to do this.

Fiona and I are going to do the northbridge/ southbridge 11+ mile thing with a charging pitstop or 2 on the beaches along the way.

[SternWake]

Fiona used to love chasing her ball into the water here, but she cut a carpal pad on an oyster shell here on one visit several weeks ago, and no longer wishes to get her feet wet.

I plugged in the portable charger and dialed it up to 6.03 amps, 250 watts, figuring we would not stay long enough to overheat the EVE 7s2p 35V battery. Fiona wanted to get rolling before I was ready to. When I unplugged barrel connector, was already up at 41.96v, amps tapering, accepting 210 watts.

We full throttled a few more miles on some nice smooth nearly traffic free asphalt, and then we walked a half mile or so to sniff and scent up a different hood, charging again at 250 watts, and I did not bother to observe what it was doing when I unplugged it and we rolled again.

Lots of hammer down full throttling for several more miles, back over the south bridge, to the park a mile from home, where I plugged in again to charge, as remote had just buzzed once indicating 35.1v which is 35.4v actual. I can easily make it home with this much battery left but I prefer to have more.

Again 250 watts charging as Fiona walked us quickly through park. Bak10s2P was above 36.4V when I hit the throttle again towards home, and then we took the long way to add a few unnecessary miles. I rode some short laps out front until the soft cut kicked in at 31.5v and decided to end it.

The portable charger was warm, by no means hot when I removed it from Neoprene I pad case on my desk.

7s2p was at 25 volts even, 3.57 volts per cell, plenty more to give, especially if I were to lower the wattage and be at a far lower amp rate when in the 2.8 volt per cell range.

If I did not carry the portable charger I likely cannot make this full loop even if going way slower, but with it I was able to keep up with traffic in the 25mph zones and get back with range to spare.

From the time I place the esk8 into the chariot and leisurely set the portable charger up delivering 250 watts, I count 16 Mississippi’s.

I could do it significantly faster if I leave the power button on and the 5.5x2.5 barrel connector hot and ready to insert.

I keep it inside a zippered neoprene I-pad holder and the fit is imperfect if I wanna zip it up everything inside with wattmeter plugged in. If the Zipper was on the short side It’d be golden.

This opportunity charging is a game changer.

If I were to try and charge a much more depleted esk8 battery for longer duration at 200+ watts, then this eve7s2p is in danger of overheating.

If I am only charging for 10 minutes or less, and can get it back upto 41.98v and amps start tapering, then I can charge and then roll as hard and fast as I want to and not overheat the Eve 35V 7s2P

The Booster itself can handle 15 amps input, even though its documentation says 10.

The CCCV booster’s load on the Eve 7s2p keeps increasing as it depletes and its voltage decreases, so I should really be lowering its output when it is down under 24 volts.

I have a bourns trimpot screwdriver and lowering the current is pretty simple. Peel up the masking tape and insert.

Seeing the wattmeter’s reading in direct sunlight is a challenge and polarized sunglasses are a no go.

With this brief opportunity charging, and adequate cool down periods, I could bump it up to 300 watts charging, but I don’t really need to.

I could also turn down output voltage below 42 so that amps start tapering earlier and there is less risk of overheating.

The Eve 30P would have been the better choice of cell for this portable charger, but I can work with the Eve35V as long as I keep its limitations in mind

[SternWake]

We did the south bridge north bridge thing today.

7.83 amps output with a half charged 7s2p gets booster heatsink, and battery, pretty dang hot to the touch.

I have not yet added a radiant and convective barrier between V Booster and battery, but did do a 1.8 mile leg at near full speed with full airflow directly into the booster heatsink at front of chariot. and decent airflow around rest of enclosure, which was quite effective at cooling it off.

The top photo is the third chill and charge session and I dialed it down to 200 watts not for the heat, but so It could deliver more watthours before one of the 7 P groups touches 2.5v and the BMS shuts it down.

The Chariot and the Guppy are now wearing white MBS 5 stars. The Kenda k473 2.80-2.50-4 and Dico 4.10-3.50-4 tires fit them very nicely. I did not have to do any centering or tweaking to get them to not wobble or bounce. I have not yet tried to balance them. I had finished 3 yesterday and #4 this morning before our roll.

I am still using 10mm axles but made sleeves to use the 12mm ID bearings the Fivestars came with, from an aluminum tube.

I do have new 10mm inner 28mm outer proper bearings so I do not need to use a sleeve, but I do want to be able to employ the MBS AS.12 truck up front with the 12mm axle. Maybe rotate hangers to reduce the risk of cast aluminum Pivot fatigue breakage and subsequent streetface.

I also want to be able to use the Sixshooter spare tire I keep on the chariot which has 10mmID 22mm OD bearings

The 10-12MM aluminum tube was actually 12.04mm OD, so would not fit until I turned it on my drill with a file and red scotch Brite. Which is good, as the sleeve fits over the 10mm axle perfectly, no slop, and the bearings now ride on the sleeve with No slop.

I did acquire MBS bearing spacers for the 5 stars. I know one can get away without them but I feel the spacer causes both bearings and bearing seats to more evenly share lateral loading.

Tires and tubes were flipped on the rims, and they sounded very different the first few miles. Tread squirrelly squirmy again. I also pumped them a bit higher than I kept them previously. Gained a bout 2.5mph top speed too

The chariot used to have a small wobble barely perceptible in my hand at speed, which is now almost gone. The Dico 4.10-3.50-4 tires are past their half life.

These MBS 5 STARs are about 4mm narrower width than my Vevor rims with the cracked bearing seats, but fitting of the - 4 tires was nearly effortless, I cannot really easily see a more rounded tread profile from having more pinched sidewalls.

The board is running good, The portable charger is working well.

[SternWake]

Explored some new territory today.

Fiona made a hundred people smile.